Gear forming machine



Aug. 10, 1943. A. KULLMAN ETAL GEAR FORMING MACHINE Fil'ed Nov.. 29, 1938 4 Sheets-Sheet 1 iii- Wanda (And 'ITORNEYfi 1943- A. KULLMAN ETAL 2,326,368

GEAR FORMING MACHINE I Filed Nov. 29, 1958 4 Sheets-Sheet 2 /////////////l .'.le

' numfmnum:mwlnuuumnu E J1 1' I 7 I w J INVENTORj 1:7" 4 1 BY 164M MmA///M ATTORNEYS 4 Sheets-Sheet s INVENTORJ BY a 2 F [1/ M (MM ATTORNEY;

A. KULLMAN ETAL GEAR FORMING MACHINE Filed No'v. 29, 1938 Aug. 10, 1943.

Aug. 10, 1943. A. KULLMAN Er'AL 2,326,363

GEAR FORMING MACHINE Filed Nov. 29, 1938 4 Sheets-Sheet 4 1N VENTORS ATTIORNEYS v Patented Aug. 10,1943

Ohio

. This invention relates to g ar Egfindingshaving, vor 'cuttingimachinermam is particular-1y fli- 700mm,; Cincinnati, oiiim'gao' oration off 7 resulted in a constr uction. wherein "the 't'e's rested rto the-antwczf testingnrrnhecking t'gears which are being iormed, to size; rnnout, and

tooth c.ontcur.-*- i r In the past, it has been necessary'to remove to place-it in .a::gear--testing ktnre tin order to inspect :it 7 forsize, runout, ami tooth contour; If the inspection showed that additional work was necessary,':the operator placed zthegear back in the machine; rNow -in setting .thegear back in the machine, there has aiway's been thecdifiiculty the tooth. 1 This is apre'requisitei-to theprcdnc tion of an accurategear.

the gear, being iormecL machine and l given range; iandiwhich is easii I Also, for examplain-ithe case'ofa'lgrinderijit has been necessary-for the operator to rely ex.- clusively on the micrometer screw of the-grinder. for lowering the grinding -wheel-sufiiciently'qtio remove the final'amountiofgstock; The wear of the grinding wheei,;due--to. wear'while, making-the cuts, and inaccuracies in :the screw? have "been conditions making it diificult to; produce a; gear whichis really ofgtheprdpersize; it

"Finally, the first gearrhadto be'finspected for sizeg ibefore the machine operator; would know haw much to lower :the grinding wheel .for sizing the next gear. 'This involved a iossof productive time, and againjthe screw-inaccuracies and wheel wea prevented the second jgea'r from being properly ground in the machine: w

- ltzhas been the object of the present inventors "tczprovide means in azgear forming machine for checking the ,size, runout; and "tooth contour of the gear concurrently withthe'jforming .of t'he gearsf Elhi-s pbjective has-resulted in a novel-coin bination 'vvherein -the workvcenx be continued nntilit "isindicated thatthe 'gear is. accurately v produced and regardless of the-'inaccuracies ocj curring because of we r of the machineipartsi' After the gear is removed from .them'achinej 'rio further inspection issnecessary, 'a-stheappara tus has indicated fully-to thenperatoie the 'trueness v lt has heenthe. iurther object of flieinveiitors .to provide a- Bea-rimming 'machine; including- 7 nieans of this character, which iswanable "of concurrentlytest n and indicating: the amount cym tai yet to nei' removsct which me ns-W 11 operate with respectttn gieagrsin' awide'rainge of sizes 7 -rtherniore, thepreseriir'inventiofri igreadi 1;; iacilitatesthe"operation 11f iriserzting 'fithe gear I 'ofiithe-=aiibor.'zand mica-m positioinawhileithe"' gear'fis in-ipo'sition, the element :is 'permitted to moveiintojengagement;:

, --0therob jects and'certain a'dva more fully-apparent in a description iof the ;a

the .geai.v ":5

ingtoward the farborsand grinding wheelvof the I rrFigureais a; sectionalvievv tahen on .li'igm'ev 1, illustrating the details 50f construction 1 of the 'te'stingiapparatiism Figurei 4,? showing :fiirther details;

to hold the main dial-siide-in d'raWn back pos1-'- V -i- 1 "tion', in released positioncwhile thegear-is being Figure: 1 abut;showingrtheqapparatns in initial position as determined by master discs and-also diaL- Cincinnati Q L1;

001 Works element, after. setting-may bejdtawn hack clear ear is. being placed on the: arborf After the- .Itha'sibeen a'rstilliurther object of the present f inventors to provide a" geartesting; apparatus which is unusually accurate in its foperati'on; I which is jinniversailyapplicable to gears gear within a wide range.- r ntagesi companyingzdrawings in .v'vhichi v V 'z-Figiire-flisiza fragmentary toplpla'nl view-oia portion of'a grinder in'corporatin'gfithe present improvements and showing the :.'apparatus 5 in position whenthe work ;0n th-e gears is finished.

V- Figure 2.is asideview ofthe machine of Figure 1,5 showing the testing apparatus in relation to s Figure 3i's aneiidijviewm theiapparatosioo grindingiimachine;

;,:Figure 5 is a sectional .v evv *t akenon; line -Figure6 is a-sectionalvi'evvI taken OnJine s Figure, ,4, shovring'rthe detent, which is-adapted ground andche'ckedu I jgFigure '1'? is asiragmentary top plan iviewiof a portion of Figure-1, illustrating the slide locked back and'out ofuse, Whilethe gear,- to, be ground;

iszbeinghplaced' on the arbor. i a r r Figureifi isi. atop plan: vieweataken similar to illustrating the operation andiuse of" th e'auxilia'ry .JZFigure-Q isa viewr'ktaken similar o-'Figur.e"8 butishowingxthe apparatus in position.justiaftei'i the gears;-.to:x "groundghave" been placedfioni the arloor q'the View 'iliusti'atin a'mot'intjotmetalpto'belrern :The improvedma'chihe gen parentthat either discs or masterigears used in initially setting the slide.

Referring specifically to the drawings, the bed' 7 or a grindingmachine is indicated at in. -The'. work arbor is :shown at ll. and the grinding iwheel at l2. "The testing apparatus, indicated with respect to the gearbeing ground. Originalthe master gear matching the gear to beground,

this indicator will show deviations from trueness in graduations varying from'zero. When the indicator remains. at zero, plus or minus the allowed toleran cejpr a complete revolution or the gear, the operator; knows that the: gear is right. It is arranged that" a single set of 'master gears or discs may provide for setting of the. testing device for any size of gear to be. ground within the range of the device; For this ,pur-

pose, an auxiliary indicator is provided andthe slide is, reset with respect to this indicator by ;means of a.. measuring rod and a 'micrometer, after the slide has been set to zero for the master gears or discs. ;Any set of master gears ofknown pitch diameter of discs of knowndiameter are' V first mounted on the. work' arbor. and. slide,-v

spin'dle. Both indicators are set at zero, the" auxiliary rindicator being held in:- compression by the conventional measuring rod .or; rods and an; end measuring micrometer. The measuring ;ro'd' orrods and; micrometer. are set: "to com;-

5 pensate forth'e difierence in distance between the centers of the set-upmating masters and the'centers of the gear of final size and the testinggmatingmasteimc arried 'bythesliden The 'iposition of the slide isjthen changed to'setthe auxiliaryeindicator b'ack to'zero; It" will be apmaybe machine-iadjacent the arbor; The arbor 151 mounted on the .conventional'centers 14 and carries the gear=or gears to be :ground, indicated at I5. 7 The master gear 16 of the device is jour nalled on a short shaft l'l'in the bifurcated forward ,endof the upper slide I8." The shaft l1 The main-slideelement 20' is mounted for translative-movement onthe dovetail 2| ofthe slide support element '22. The 'slidesupport'element 22'- is mounted for lateraladjustment onl a base ll inr'a slot 24 thereof.'j1'T-bolts -25, 'engagedin a .T-slotiiiof the base, traverse the attachment lugs 2lof the slide' support 22 and fix the slide' support in any desired lateral position.

' The slide 29 is adjustably mounted in the; way I ofth slide" support l2. The adjustmentis pro-v 'cur'ed by means of a screw 28 disposedithrough 1y set tozero, with the master gear in mesh with g opening'i's'closed by'means of a cap 45.

A coil spring 39, under compression, is-centered upon these studs between the lug and the mentioned wall. Thus, the slide element I8 is constantly'urged inwardly and the dial indicator 34 is released. This spring is effective for con- 4 stantly urging the master gear against the gear being tested and, as the gear is ground,'relieves the contact 'of the indieator'stem lll with the abutment gate 4|, whereby "the indicator moves toward zero position.

An opening 44 is provided in the top slide sec- 7' tion .18 providing access .to the cavity 36 for spectto, a ClI'ClllflIldiEtI -EU, the readings of which range from zero u'ptoififty' in either direction.

;The-finger.is operated, by *meansof the stem,

against .1 constant pressure 'means Wvithin i the gauge (not shown). By movingsth'e stem a definite amount, the finger will be moved to zero position. The-mechanism of the gauge'is built into the .top slide section and is covered by means of aT-coverplate:5l, hinged on 9. lug 52 onapinj5 3. I V. I 'igAs previously stated, the mechanism,-{ described thus far, would requi're' mating-"master "gears' for each 1 size) of gear to be ground.

Obviously, a'g'reat manyhmaster-gears would be required- V and the expense WouId be high when the work is in'ismallq;lot quantities and'of big variety. f 1i 1 lAccordingly -the' device-is provided with an auxiliary mechanism which reduces tooling to a minimum. A' 'sec'ond dial' indicator 55 is 'pro vided;"'I'hisdial ihdicatdris of' thesame type includes a knurled head-facilitating removal of the-shaft for dismounting the gear. '-..'Ihe slide l8- is 'mounted 'for' trar'isl'atiye' movement on'the dovetail .way 'l9'o1fethe main'slide element 29."

as the main one and is'mountedon a bracket 56' -fhred to the'side 'offth'e base '23 and including a'trou'gh SIJTA bracltet:58"is fixed to the saddle or slide Zllf-which carries the; upper or "master, gear carrying slide' l flf fjThis bracketprovides'a lug 59 'exten'ding to a *position' over the trough.

The stem; of the second-dial indicator projects toward this lug; and a measuring rod or ro'ds t l and aymicrometr 62 areinserted -between'the V stemahd the contact point 63 of the-bracket.

Figure 8) or any ;set.0f master gears; of known a clearance slot 29 of the support parallel to the a way; Thisscrew is rotatably journalled" at the forward endiof the support in abushing 30 and 'hasa hand wheel 3lIfiXedon its extended end. Thescrewtraversessa nut 32 fixed to the slide by screws 33.

' V The. slide is sectional, and .thelupper member 1,8,.- which carries Ltheindicator 34, hasa predeterminedz'a'mount-fofl' movement relative to the main'slide" elementi'flfl; For thisipurpose, the

element I8 is mounted in a dovetail slideway l9 7 ain-theslideielement 20. A=lug=35 isfixed' on the ,slide' element 20.;ifIt projects upwardly into a: cavity 36 in the;underside of theelement I81 :A

. centeringstudjlis;fixed in one sidejof thelug adjacent-Jo, and: axially ;-,alignedwith .}another stud 39fixedin the opposing wall of .the cavity. 7

r Now in setting up thedevice'for anygiven piece a of work, any two' discs ofknownj diameterflsee pitch diameter are mounted on th'e'w'ork spindle or arbor and the slide, as" described heretofore.

Nowithe slide is adjusted to set the first in dicator 34- to zero and the secondindicator 55" is setat zero by-placing the conventionalmeasurmggrods; and end measuring micrometer in the trough 51. Appropriate adjustments are made on. 'w

. the micrometer to bring-the second" indicator to zero:-

KnowingtheI final, pitch diameter of the gear to be ground and the pitch diameter of the mating master, the measuring rod and micrometer are 'changed'and' reset, afterremoval of the master gears, to compensate forthedili'erence in centers: 7 TheMposition ofmthe' sadd1e=or slide 1 i then 7O changdytherods and micrometer inserted in the trough, 'andthe slide adjusted, to bringthe second dial indicatorrback to zero; Thereupon, the work, tobei'ground, and the mating master,

1 are substituted for'the discs. The device is then readytyindicate the size of the work; as it is trough, and the micrometer 7 When the operator Wishes to insert the Work on the arbor, he can move the slide back and lock it in position by means of the locking detent pin 65 detailed in Figures 6 and 7. .This detent pin provides anoperati-ng head 66 and a spring-- urged inner end 61 normally riding against the side of the top slide. This pin drops into a notch 68 in the slide, when the slide is drawn back to the position shown in Figure 7, and after the.

gate 4| has been lifted.

It is believed that reference to Figures 8 and 9 will make clear the operations of setting up the machine for a given gear grinding operation.

The master discs 69, 69am shown in position. The gate 4! is down and the first dial 4 is-at zero. The slide or saddle has been moved forwardly so that zero reading is obtained byappropriate contact between the master discs. The measuring rod and the micrometer are in the so as to set the second dial at zero.

'Thereupon, the measuring rod is removed, in this case, and the micrometer changed so that the total length of the micrometer is less than the total length of the previously set micrometer and'the measuring rod by a distance exactly equal to the difierence between the' centers of the master discs and the centers of the master ear and a gear of the finished size. 7

Now, as shown in Figure 9, the rough gear or gears l5, I5 are in place. The engagement of these gears with the master gear on the slide, of course, moves the first indicator 3 from zero, and indicates, on thegraduations, the amount of material to be ground. This movement of the slide is only a movement of the top section thereof. The main section of the slide will remain in'fixed position. Obviously, the operator can remove the micrometer for he then knows that the slide has been properly set.

has been adjusted the first named slide moves toward the gear movement of the second mentioned element, an extension on said first mentioned element, a

second indicator mechanism, anda support for a measuring instrumentalityadapted to be dis-.5;

posed between said extension andv said second indicatormeans, whereby the compound slidef may be reset, after initial setting, a predeter mined, measured amount as; determined by change in the measuring instrumentality.

3'. In a gear forming machine, means forv ro tatably supporting a gear to be formed, means for forming said gear, a slide mounted thereon, a p

master gear mounted onthe slide in rolling mesh with said gear tobe formed, a gauge operated by said slide, said gauge including a stem for,

operating the pointer thereof, an'adjustable slide carrying said first named slide and providing an abutment for said stem, and spring means between said slides for urging said first named slide-toward the gear being ground, whereby,.as

being formed, the pointer approaches zero,

4. In a' grinding machine, a base, an arbor for supporting a gear to be ground, means for grinding the teeth'of said gear, a slide mounted on It might be added that'Figure 1, illustrates the position of the gauges when the work ha been fully ground. By watching the first gauge, the operator is able to tell just when the grinding is approaching completion. Specifically, he can determine the amount of runout, and the size and is able to detect any inaccuracy a to each; I tooth.

Having described our invention, we claimi 1. In a device'for testing a gear being ground,

a slide, a gear mounted on the slide in rolling mesh with the gear. being ground, a gauge mounted on said slide including an indicator, said gauge including a stem for operating the indicator, an adjustable slide carrying said first named slide, a removable abutment, for said stem mounted in said second slide, and spring means between said slides for urging said first named slide toward the gear being ground, whereby, as

the first named slide moves toward the gear being ground, the indicator approaches zero.

said base, a master gear adjustably mounted on said slide and disposed in mesh with the gear being ground, and a dial operated by said master gear for indicating the runout, the variations from'finished size, and variations in contour of the teeth of the gear.

5. A device for testing-the trueness pr me teeth of a gear being formed; comprising, a base,

a slide mounted on thebase, agear mounted 5 on the slide in rolling mesh with. the gear being formed, a second slide ment of saidslides, spring means between said slides-for urging said first-named slide the gear being formed, meansfor adjusting and of the second-named slide,, a 3 second indicator mounted on the base,"a 1pro. ,J'ection from the second-named slide, and'fafif'."

measuring instrumen} tality between the extension and said second.

fixing the position means for supporting a indicator. 7

6. In a gear forming machine, a base, an arbor for supporting a gear, means for removingmetal from the teeth of said gear, a slide mounted on said base, a master gear mounted on said slide and disposed in mesh with. the gear, and a dial operated by said slide for indicating the trueness of the teeth of thegear.

ALFRED CHARLES BLACK.

carrying said first-named slide, an indicator operated by relative move- 

